1 files changed, 91 insertions, 0 deletions
diff --git a/src/ipa/ipu3/algorithms/awb.h b/src/ipa/ipu3/algorithms/awb.h
new file mode 100644
index 00000000..fac54e45
--- /dev/null
+++ b/src/ipa/ipu3/algorithms/awb.h
@@ -0,0 +1,91 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2021, Ideas On Board
+ *
+ * awb.h - IPU3 AWB control algorithm
+ */
+#ifndef __LIBCAMERA_IPU3_ALGORITHMS_AWB_H__
+#define __LIBCAMERA_IPU3_ALGORITHMS_AWB_H__
+
+#include <vector>
+
+#include <linux/intel-ipu3.h>
+
+#include <libcamera/geometry.h>
+
+#include "algorithm.h"
+
+namespace libcamera {
+
+namespace ipa::ipu3::algorithms {
+
+/* Region size for the statistics generation algorithm */
+static constexpr uint32_t kAwbStatsSizeX = 16;
+static constexpr uint32_t kAwbStatsSizeY = 12;
+
+class Awb : public Algorithm
+{
+public:
+	Awb();
+	~Awb();
+
+	void prepare(IPAContext &context, ipu3_uapi_params *params) override;
+	void process(IPAContext &context, const ipu3_uapi_stats_3a *stats) override;
+
+	struct Ipu3AwbCell {
+		unsigned char greenRedAvg;
+		unsigned char redAvg;
+		unsigned char blueAvg;
+		unsigned char greenBlueAvg;
+		unsigned char satRatio;
+		unsigned char padding[3];
+	} __attribute__((packed));
+
+	/* \todo Make these three structs available to all the ISPs ? */
+	struct RGB {
+		RGB(double _R = 0, double _G = 0, double _B = 0)
+			: R(_R), G(_G), B(_B)
+		{
+		}
+		double R, G, B;
+		RGB &operator+=(RGB const &other)
+		{
+			R += other.R, G += other.G, B += other.B;
+			return *this;
+		}
+	};
+
+	struct IspStatsRegion {
+		unsigned int counted;
+		unsigned int uncounted;
+		unsigned long long rSum;
+		unsigned long long gSum;
+		unsigned long long bSum;
+	};
+
+	struct AwbStatus {
+		double temperatureK;
+		double redGain;
+		double greenGain;
+		double blueGain;
+	};
+
+private:
+	void calculateWBGains(const ipu3_uapi_stats_3a *stats);
+	void generateZones(std::vector<RGB> &zones);
+	void generateAwbStats(const ipu3_uapi_stats_3a *stats);
+	void clearAwbStats();
+	void awbGreyWorld();
+	uint32_t estimateCCT(double red, double green, double blue);
+
+	struct ipu3_uapi_grid_config awbGrid_;
+
+	std::vector<RGB> zones_;
+	IspStatsRegion awbStats_[kAwbStatsSizeX * kAwbStatsSizeY];
+	AwbStatus asyncResults_;
+};
+
+} /* namespace ipa::ipu3::algorithms */
+
+} /* namespace libcamera*/
+#endif /* __LIBCAMERA_IPU3_ALGORITHMS_AWB_H__ */